1. Field of the Invention
The present invention relates to power supply control circuit modules including a plurality of switching regulators.
2. Description of the Related Art
At present, higher packing densities of circuit elements are required for circuit modules for use in communication devices. Thus, such a circuit module is generally made from a multilayer body, which is formed by stacking a plurality of dielectric layers that include electrode patterns, and surface-mount type electronic components which are to be mounted on the multilayer body.
In such a circuit module for use in a communication device, a communication control circuit and a power supply control circuit are formed in the multilayer body, as illustrated in Japanese Unexamined Patent Application Publication No. 2009-231606. The communication control circuit includes a communication control IC element mounted on a surface of the multilayer body. The power supply control circuit includes a DC-DC converter switching IC element mounted on the surface of the multilayer body.
In this conventional circuit module, heat dissipation efficiency of the DC-DC converter switching IC element is being increased by mounting the DC-DC converter switching IC element on the surface of the multilayer body, namely the surface on a side opposite to a side facing a mother board when the multilayer body is mounted thereon.
In the foregoing conventional circuit module, however, electrode patterns for connecting the DC-DC converter switching IC element to other circuit elements are determined based on positional relationships between the DC-DC converter switching IC element and the other circuit elements. Thus, depending on the positional relationship, there may be a case where the heat dissipation of the whole DC-DC converter circuit is not adequate, not only in the DC-DC converter switching IC element but also in the electrode patterns, etc, which is positioned on a output side of the DC-DC converter switching IC element and through which large currents flow.